From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.15.19]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mout.gmx.net", Issuer "TeleSec ServerPass DE-1" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 0E72921F779 for ; Sun, 1 Nov 2015 08:05:12 -0800 (PST) Received: from hms-beagle.home.lan ([217.237.68.126]) by mail.gmx.com (mrgmx001) with ESMTPSA (Nemesis) id 0LaooK-1aLc6P38Aq-00kLiM; Sun, 01 Nov 2015 17:05:09 +0100 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Sebastian Moeller In-Reply-To: <563611DE.5080304@darbyshire-bryant.me.uk> Date: Sun, 1 Nov 2015 17:05:45 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: References: <563517E5.4050202@darbyshire-bryant.me.uk> <7F32378C-878D-437C-B56C-F8E5B0D99895@gmx.de> <563611DE.5080304@darbyshire-bryant.me.uk> To: Kevin Darbyshire-Bryant X-Mailer: Apple Mail (2.1878.6) X-Provags-ID: V03:K0:YCcRK+O0mBPMe4V3NyONp8C5d9rJZjY/V4jlvvpMSanfRsVVQgm 7Yq96X3/18+b+hPidjqIrdjBKUQwrJNcgQSd8TWGXvEO9qKEqr8YTe6xAoOXjniDmwZiZHN CE7H4hb+kY7k2Q111hH0F56OrFHhGtiNVgQnMbFUn2l7A4T/Umg+KnfGPOPxREbTmkH1p2g z8qYcPyf5I9dqDx1oM2QQ== X-UI-Out-Filterresults: notjunk:1;V01:K0:qI9QsjZQ7RI=:PLafP+9r/iSwSwgPktux5V Vbn1263grhd7CWw8krciCYj13KWiXDzLDOmW3JlQJo9f4aANbr8xoREWWFRUBVHA7aU+2xUe7 Uv6bAizhw8JqV2BXJyg9vax6/y6w1SGEw8pmganfeaPLlVhDekG1u+41W4lmOxLJyBGSnKpDR Zlbr5k1HNl4BCyMld8WJUmmHuolRkq3dcxA0tfaL7XS+ifIl62fs6Fob7vIBaqBPIBTnWCV3G 5fZ2GxjPiOz67Rd87/oiFcIpwrui160Z4IJL5okBBiSja6RxG3X6vZBwVueZsIDRE7vwwwO6+ dRR+eMflDmHPUfGbUxZvJiQnZG8Hyq395To1MBw2px3upu8uix7qnOtdFBkQdsKOkQCtLsLyu +1VQBOmTuBnpPqMFSpw3NqFK7N8KWxONg62G7v1VGrn47mXeO9q8lNQb7k52pm9uoCKBr4YJH 345jDFacaSK1fpiD6m6NDEvOiFG3AGsNiitZfOT1IGLbUYnlXJQMqctawBKisFOSosyS/EDqO 7lrU2WGHqc92Ovj7mmn03NAuwOmVXDS9AptlaleCXejMc1/JH+2LoLsIRQzkCWVufm7tPmoQt BQ4Y2T/MGjhYR0LwSnMcAsRGFhfGiIi4sj/gr1MbhxKOB/I/LGLjLC3lyThaXJ/1bRR9j2thm hQMOMv/Zl3HQ1tk1iV/mASnlcKyG/d6giw3ZFqenFrXJFOJ8kA4mBIiY7KHPCzXbzLg47lsN2 DAyjPoBZ6BGnwgq9ZAQuDo51EweeWboisEgMnbgfYJEiOkB899nK429VZv/ZafyugNDEvTtEl gjhtM7j Cc: cake@lists.bufferbloat.net Subject: Re: [Cake] Stranger target behaviour X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 01 Nov 2015 16:05:35 -0000 Dear friends of cake, On Nov 1, 2015, at 14:21 , Kevin Darbyshire-Bryant = wrote: > On 01/11/15 09:47, Sebastian Moeller wrote: >> Hi there, >>=20 >> On Oct 31, 2015, at 21:29 , Dave Taht wrote: >>=20 >>> The second one is from the interval >> 4, which equates to 6.2ms. I >>> note I picked that because some early data (2012) we had showed that >>> target slightly greater than cable media acquision (6ms) time was a >>> slight win, and it did not hurt to use a number more evenly = divisible >>> in binary than the arbitrary 5%. >> Well, but should it not be 6.2ms even if no rtt is explicitly = requested? Currently cake has a lot of corner-cases that are not too = well documented either. > Sebastian as ever picks up on the exact source of my confusion/point. >=20 > If 'target=3Dinterval/16' is the new mantra then the defaults built in = to > cake qdisc should be changed, otherwise we have the current situation > which is: Default Interval=3D100ms, target=3D5ms. If I specify rtt = 100ms > via the joys of tc, then I have: Interval=3D100ms, target=3D6.2ms. If = I > specify a target keyword such as 'internet' which also has an = interval=3D > 100ms, then target become 5ms again. Somewhat inconsistent. I believe I just fixed this by initializing target in sch_cake = to "interval >> 4=94, I opted for the calculation instead of the simple = number 6250 to sort of document the pattern and tried to put in a = comment explaining why this is okay with codel's theory. Please note, I = did not really test this, so for all I know it might break = spectacularly... Slightly different question, I have a few cosmetic changes for = tc, so which repository to commit this too, is tc-adv to be the = gathering point for changes to be considered? Best Regards Sebastian=